docs: def kernels(gandi, vm, datacenter, flavor, match):
      """List available kernels."""
  
      if vm:
          vm = gandi.iaas.info(vm)
  
      dc_list = gandi.datacenter.filtered_list(datacenter, vm)
  
      for num, dc in enumerate(dc_list):
          if num:
              gandi.echo('\n')
          output_datacenter(gandi, dc, ['dc_name'])
          kmap = gandi.kernel.list(dc['id'], flavor, match)
          for _flavor in kmap:
              gandi.separator_line()
              output_kernels(gandi, _flavor, kmap[_flavor])